Function gui_register

src/lua-engine.cpp:4824–4846

function gui.register(function f) This function will be called just before a graphical update. More complicated, but doesn't suffer any frame delays. Nil will be accepted in place of a function to erase a previously registered function, and the previous function (if any) is returned, or nil if none.

//  a previously registered function, and the previous function
//  (if any) is returned, or nil if none.
static int gui_register(lua_State *L) {

	// We'll do this straight up.


	// First set up the stack.
	lua_settop(L,1);

	// Verify the validity of the entry
	if (!lua_isnil(L,1))
		luaL_checktype(L, 1, LUA_TFUNCTION);

	// Get the old value
	lua_getfield(L, LUA_REGISTRYINDEX, guiCallbackTable);

	// Save the new value
	lua_pushvalue(L,1);
	lua_setfield(L, LUA_REGISTRYINDEX, guiCallbackTable);

	// The old value is on top of the stack. Return it.
	return 1;

}

// table sound.get()
static int sound_get(lua_State *L)